Report to the Subcommittee on 

Tactical Air and Land Forces, 

Committee on Armed Services, 

House of Representatives 

United States General Accounting Office 

GAO 

June 2003 DEFENSE 

ACQUISITIONS 

Matching Resources 

with Requirements Is 

Key to the Unmanned 

Combat Air Vehicle 

Program’s Success 

GAO-03-598 
The UCAV program’s original performance objectives posed manageable 

challenges to build an affordable, highly survivable, and lethal weapon 

system. The Air Force, however, added requirements for electronic attack 

and increased flying range after DOD accelerated the program’s product 

development schedule by 3 years. These changes widened the gap between 

the customer’s requirements and the developer’s resources, specifically time, 

reducing the probability that the program would deliver production aircraft 

on cost, on schedule, and with anticipated performance capabilities. 

DOD has recently decided to adopt a new joint service approach to UCAV 

development that provides more time to close the requirements—resource 

gap before product development starts. It appears DOD may add new 

content because it is proposing to build a new prototype that would be a 

larger air vehicle, capable of flying and carrying out combat missions for 

longer periods of time. To reduce technical risk, DOD anticipates delaying 

the start of product development for several years in order to address new 

requirements. 

As a gap between resources and requirements widened in 2002, risks 

projected for the start of product development with UCAV’s 15 technologies, 

processes and system attributes increased significantly. The new joint plan 

brings the risks back down. This action also allows competition back into 

the UCAV development effort. 

DOD will still face challenges in controlling joint, multimission requirements 

and ensuring that both services continue to provide funds for the program 

while also funding other large aircraft investments. If these challenges are 

not met, the gap between requirements and resources could resurface. 

DOD’s role will continue to be instrumental in helping to negotiate 

requirements, assure resources are in place, and make difficult program 

trade-offs. 

Risk Levels Projected at Start of Product Development under Different UCAV Plans 

The Department of Defense (DOD) 

is developing a new unmanned 

combat air vehicle (UCAV) that can 

suppress enemy air defenses and 

conduct other air-to-ground 

attacks, particularly against heavily 

defended targets. Because it may 

perform these missions at a 

relatively low cost, the UCAV could 

be used to replace some of DOD’s 

aging tactical aircraft fleet. A key to 

UCAV’s success will lie in DOD’s 

ability to match users’ needs, or 

requirements, with the developer’s 

resources (technology and design 

knowledge, money, and time) when 

product development begins. Our 

work shows that doing so can 

prevent rework and save both time 

and money. Therefore, we assessed 

DOD’s ability to make this match. 

GAO conducted its work on the 

basis of the Comptroller General’s 

authority and addresses the report 

to the Subcommittee because of its 

interest and jurisdiction in the 

program. 

We recommend that DOD develop 

a joint UCAV acquisition approach 

that balances requirements and 

resources at the start of product 

development. We also recommend 

that the Secretary formalize the 

UCAV management role performed 

by his office, ensure that the 

services are fully involved in the 

process, and work to develop an 

efficient approach to transition the 

UCAV to the product development 

phase so the needs of the war 

fighter can be met more quickly. 

www.gao.gov/cgi-bin/getrpt?GAO-03-598.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Paul Francis at 

(202) 512-2811 or francisp@gao.gov. 

Highlights of GAO-03-598, a report to the 

Subcommittee on Tactical Air and Land 

Forces, Committee on Armed Services, 

House of Representatives 

June 2003

DEFENSE ACQUISITIONS 

Matching Resources with Requirements 

Is Key to the Unmanned Combat Air 

Vehicle Program’s Success 
Page i GAO-03-598 UCAV Program's Success 

Letter 1

Results in Brief 2

Background 3

Importance of Matching Resources with Requirements before 

Product Development 5

Gap between UCAV Resources and Requirements Was Increased 

in 2002 7

Recent DOD Decision to Restructure Program Can Reduce Risks 14

Conclusion 19

Recommendations for Executive Action 19

Agency Comments and Our Evaluation 20

Scope and Methodology 20

Appendix I Comments from the Department of Defense 22 

Tables 

Table 1: Current Risk Level of UCAV Technologies, Processes, and 

System Attributes 9

Table 2: Chronology of Changes to the Air Force UCAV Acquisition 

Program Schedule Since 2000 11

Table 3: Comparisons of UCAV Variants 14

Figures 

Figure 1: Boeing X-45A Demonstrator in Flight 4

Figure 2: Computer Rendition of the Boeing X-45B Prototype 5

Figure 3: Timing of the Match between Customer Requirements 

and Resources 7

Figure 4: Effect of Accelerated Product Development Start on 

Program Risk 13

Figure 5: Computer Rendition of the Boeing X-45C 15

Figure 6: Computer Rendition of the Northrop Grumman X-47B 16

Figure 7: Effect of Delayed Product Development Start on 

Program Risk 17

Contents 
Page ii GAO-03-598 UCAV Program's Success 

Abbreviations 

DARPA Defense Advanced Research Projects Agency 

SEAD suppression of enemy air defenses 

UCAV Unmanned Combat Air Vehicle 

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Page 1 GAO-03-598 UCAV Program's Success 

June 30, 2003 

The Honorable Curt Weldon 

Chairman 

The Honorable Neil Abercrombie 

Ranking Minority Member 

Subcommittee on Tactical Air and Land Forces 

Committee on Armed Services 

House of Representatives 

The Department of Defense (DOD) is in the initial stages of developing a 

new unmanned air vehicle capable of suppressing enemy air defenses 

and carrying out other types of air-to-ground attacks, particularly against 

heavily defended targets. Because of its potential to perform these 

missions at a relatively low cost, this new air vehicle could foster efforts 

to replace DOD’s aging tactical aircraft fleet. 

The air vehicle is being developed under the Unmanned Combat Air 

Vehicle (UCAV) program. This is an advanced technology demonstration 

program, still in a pre-acquisition phase, with two demonstrator UCAVs 

being flown to assess technologies and capabilities. Launch of a formal 

product development program was expected to occur next fiscal year 

but has since been delayed. We conducted our work on the basis of the 

Comptroller General’s authority and have addressed the report to you 

because your expressed interest in the program as a committee of 

jurisdiction. 

The start of product development—signified by a Milestone B decision—

represents the point at which program managers make a commitment to 

DOD and the Congress that the UCAV will perform as required and be 

delivered on time and within estimated costs. Our work has shown 

that programs are more likely to succeed if program managers are 

able to achieve a match between user needs, which eventually become 

requirements, and resources (technology, design and production 

knowledge, money, and time) at the start of product development. 

Conversely, if they do not match requirements with resources, cost 

overruns and schedule delays are likely to occur, reducing DOD’s buying 

power in other areas. 

United States General Accounting Office

Washington, DC 20548 
Page 2 GAO-03-598 UCAV Program's Success 

Consequently, this report analyzes requirements1 and schedule changes 

made during pre-acquisition and their effects on DOD’s ability to achieve 

this match. The report also assesses a recent decision to expand the 

program—both in terms of the military services that will be involved with 

it and in terms of the design and capability of the air vehicle—and that 

decision’s effect on DOD’s ability to match requirements to resources. 

Our report focuses on the UCAV program managed by the Air Force and 

the Defense Advanced Research Projects Agency (DARPA). DARPA 

has also been working with the Navy on a UCAV, but until recently its 

transition to the product development phase was further off in the future. 

We did not assess the Navy’s effort except to the extent that it was 

included in the recently established joint program. 

From 2000 through 2002, decisions to get more capability in less time 

widened the gap between UCAV resources and requirements. The UCAV 

program’s original requirements posed significant, but manageable 

challenges to build an air vehicle that is affordable throughout its life 

cycle, highly survivable, and lethal. Subsequently, however, the Air Force 

added requirements for an electronic attack mission and increased flying 

range. Also, DOD accelerated the program’s product development 

schedule by 3 years. Those actions widened the gap between requirements 

and resources and increased the challenge for the development program. 

DOD has recently decided to adopt a new joint Air Force and Navy 

approach to UCAV development that provides more time to close the 

requirements-resource gap before product development starts. Details 

concerning the new acquisition strategy behind this approach have not 

yet been worked out. However, the program could increase requirements 

since DOD is proposing to develop a new prototype that would essentially 

be a larger air vehicle, capable of carrying out combat missions for longer 

periods of time. DOD currently anticipates delaying product development 

by several years in order to address new requirements. This delay would 

help to reduce technical risks, but initial fielding of the new air vehicle 

would be delayed as well. Having the Air Force and the Navy work jointly 

on a UCAV program is more efficient than two separate programs. At the 

 1

 Formal requirements for the UCAV program have not yet been established. However, 

program objectives based on customer expectations have been established for specific 

missions the UCAV is expected to perform. We refer to these as requirements in this report. 

Results in Brief 
Page 3 GAO-03-598 UCAV Program's Success 

same time, the participation of two services will increase the challenges 

of sustaining funding and managing requirements. 

GAO is making recommendations to the Secretary of Defense on 

maintaining flexibility to make the tradeoffs necessary to bring and 

keep the UCAV’s requirements and resources in balance and to ensure his 

office maintains the constructive role it has played in the program so far. 

DOD has been successfully using unmanned air vehicles such as the 

Global Hawk and Predator to gather intelligence and perform surveillance 

and reconnaissance missions for military purposes. Beginning in the 

mid-1990s, DOD began to conceive of a different type of unmanned air 

vehicle—the unmanned combat air vehicle or UCAV—which would be 

capable of performing dangerous, lethal combat missions, including 

suppression of enemy air defenses (SEAD).2

 Unlike other unmanned air 

vehicles, UCAVs would carry weapons as well as electronic jammers to 

confuse enemy radars. DOD also envisioned that the air vehicle would 

operate more autonomously than other unmanned air vehicles, requiring 

little or no human input from ground stations to complete their missions 

or change flight paths. In addition, UCAVs would be stealthy and capable 

of flying in groups or with manned aircraft. 

The potential of these weapons has garnered high interest from both 

Congress and DOD. In the fiscal year 2001 Defense Authorization Act, 

Congress set a goal that by 2010, one-third of DOD’s deep strike force be 

unmanned in order to perform this dangerous mission.3

 In addition to 

the potential for saving lives on risky missions, the UCAV could provide 

mission capability at less cost than manned aircraft. Program officials 

initially aimed for the UCAV’s acquisition cost to be one-third of the joint 

strike fighter and operations and support costs to be at least 75 percent 

lower. Because of the promise of unmanned air vehicles, the Office of 

Secretary of Defense has established a joint-service unmanned air vehicles 

task force to help promote the development and fielding of these systems, 

including making sure that there is multiservice cooperation. This task 

 2

 Suppression of enemy air defenses (SEAD) missions are those directed at destroying or 

interrupting the ability of ground-based missiles, either fixed or mobile, to locate, target, 

and/or destroy U.S. aircraft. 

3

 Pub. L. No. 106-398, Sec. 220 (2000). 

Background 
Page 4 GAO-03-598 UCAV Program's Success 

force is responsible for outlining the future of DOD’s unmanned 

air vehicles. 

In the late 1990s, DARPA and the Air Force began pre-acquisition efforts 

to conduct advanced technology demonstrations to show the technical 

feasibility of using UCAVs to penetrate deeply into enemy territory to 

attack enemy targets. Boeing Corporation was selected in 1999 to 

develop and demonstrate two demonstrator UCAVs—designated X-45A. 

(See fig. 1.) 

Figure 1: Boeing X-45A Demonstrator in Flight 

The DARPA-Air Force UCAV original plan also called for building and 

demonstrating two prototypes during the pre-acquisition phase, called 

X-45B, that are larger and incorporate low observable technology. 

(See fig. 2.) These air vehicles were expected to be more representative 

of the operational air vehicle that the Air Force planned to field. Initially, 

the Air Combat Command, which establishes mission and performance 

requirements, determined that the X-45B should be focused on performing 

SEAD missions within the air superiority mission area. This decision 

was made to address the limited inventory of current assets in the air 

superiority mission area and to counter the challenges and deficiencies 

associated with conducting SEAD missions. 
Page 5 GAO-03-598 UCAV Program's Success 

Figure 2: Computer Rendition of the Boeing X-45B Prototype 

As of February 2003, 55 of 160 planned demonstrations have been 

completed. Most of the demonstrations designed to validate the basic 

flight characteristics of the air vehicle have been completed. Only a small 

number of the demonstrations needed to validate the ability of a single air 

vehicle to perform a preemptive destruction mission have been completed. 

The more demanding demonstrations—those designed to demonstrate 

technologies and software for highly autonomous, multivehicle operations 

(with both manned aircraft and unmanned air vehicles), and the more 

difficult aspects of the SEAD mission against mobile targets—have not 

begun. 

The product development decision that DOD is approaching for its 

UCAV program represents a commitment by the product developer to 

deliver a product at established cost, schedule, and performance targets 

and identifies the amount of resources that will be necessary to do so. 

Our studies of leading companies have shown that when requirements 

and resources were matched before product development was started, 

the more likely the development was able to meet performance, cost, and 

schedule objectives.4

 When this took place later, programs encountered 

 4

 U.S. General Accounting Office, BEST PRACTICES: Better Matching of Needs and 

Resources Will Lead to Better Weapon System Outcomes, GA0-01-288 (Washington, D.C.: 

Mar. 8, 2001). 

Importance of 

Matching Resources 

with Requirements 

before Product 

Development 
Page 6 GAO-03-598 UCAV Program's Success 

problems such as increased cost, schedule delays, and 

performance shortfalls. 

A key to achieving this match is to ensure that the developer has the 

resources—technology, design and production knowledge, money, and 

time—needed to design, test, manufacture, and deliver the product. It is 

not unusual for a customer to initially want a high-performing product that 

does not cost much or take too long to develop. But such an expectation 

may exceed the developer’s technology or engineering expertise, or it may 

be more costly and time-consuming to create than the customer is willing 

to accept. Therefore, a process of negotiations and trade-offs is usually 

necessary to match customer requirements and developer resources 

before firming requirements and committing to product development. 

Our work has shown that successful programs will not commit to product 

development until needed technologies are ready to satisfy product 

requirements. In other words, technology development is separated from 

product development. If technology is not sufficiently mature at the 

beginning of a product development program, the program may need to 

spend more time and money than anticipated to bring the technology to 

the point to which it can meet the intended product’s performance 

requirements.5

Testing is perhaps the main instrument used to gauge technology maturity. 

Testing new technologies before they enter into a product development 

program, as DOD is doing now by demonstrating the two X-45A 

demonstrators, enables organizations to discover and correct problems 

before a considerable investment is made in the program. By contrast, 

problems found late in development may require more time, money, and 

effort to fix because they may require more extensive retrofitting and 

redesign as well as retesting. These problems are further exacerbated 

when the product development schedule requires a number of activities to 

be done concurrently. The need to address one problem can slow down 

other work on the weapon system. 

Figure 3 illustrates the timing of the match between a customer’s 

requirements and a product developer’s resources for successful and 

problematic programs we have reviewed. 

 5

 U.S. General Accounting Office, BEST PRACTICES: Better Management of 

Technology Development Can Improve Weapon System Outcomes, GAO/NSIAD-99-162

(Washington, D.C.: July 30, 1999). 
Page 7 GAO-03-598 UCAV Program's Success 

Figure 3: Timing of the Match between Customer Requirements and Resources 

During 2002, significant requirements were added to the UCAV program 

after the schedule was accelerated by 3 years. This step put the program at 

considerable risk because it increased the gap between requirements and 

resources. The program added two new requirements—one for electronic 

attack capability and one for increased flying range—while reducing a 

critical resource, time, to mature key UCAV technologies. As a result, the 

Air Force and DARPA anticipated that most of the 15 key technologies, 

system attributes, or processes supporting the aircraft’s basic capabilities 

would move from all low risk to mostly medium risk of achieving desired 

functionality by the time a product development decision was reached; 

one would be at high risk. 

The UCAV program’s original requirements were difficult to meet because 

they posed significant but manageable technical challenges to building 

an air vehicle that is, at once, affordable throughout its life cycle, highly 

survivable, and lethal. In the last year, both air vehicle and mission 

Gap between UCAV 

Resources and 

Requirements Was 

Increased in 2002 

UCAV Requirements 

Increased During 2002 
Page 8 GAO-03-598 UCAV Program's Success 

equipment requirements were increased. The original requirements called 

for a UCAV that would have 

• a low life-cycle cost, survivable design; 

• a mission control station that can fly single or multiple UCAVs at 

one time; 

• a secure command, control, and communications network; 

• completely autonomous vehicle operation from takeoff to landing; 

• off-board and on-board sensors with which to locate targets; and 

• human involvement in targeting, weapons delivery, and target 

damage assessment. 

Once these requirements were established, the UCAV contractor identified 

15 technologies, processes, and system attributes the UCAV would have 

to possess to meet those requirements. These elements became a way to 

gauge the level of knowledge (in terms of risk) that the contractors had. 

Right now, technologies that support some of these capabilities, such as 

autonomous operation, are not yet mature. We used their risk assessments 

and criteria for the 15 technologies, processes, and system attributes to 

determine current system integration risk as well as technology risk. We 

believe technology readiness levels would have provided a more precise 

gauge of technology maturity, but program officials did not provide them.6

Currently, 10 technologies, processes, and system attributes are 

considered to be medium risk by the Air Force and DARPA. Medium risk 

means that there is a 30 to 70 percent probability of achieving the desired 

functionality for the initial operational UCAV. Moreover, 5 are currently 

considered to be high risk, that is, there is less than 30 percent probability 

of achieving their functionality. Table 1 provides the current risk level of 

the 15 UCAV technologies, processes, and system attributes for original 

UCAV objectives. 

 6

 A good indicator of technology risk is technology readiness level, which is used by NASA 

and some Air Force programs to define the level of risk from a technology given its level 

of demonstration. 
Page 9 GAO-03-598 UCAV Program's Success 

Table 1: Current Risk Level of UCAV Technologies, Processes, and System 

Attributes 

Characteristics currently 

at medium risk 

Characteristics currently 

at high risk 

• Affordable air vehicle unit/ 

recurring flyaway cost 

• Survivable air vehicle integration 

• Weapons suspension and release • Advanced targeting and 

engagement process 

• Dynamic distributed 

mission/vehicle control 

• Low observable maintainability 

• Advanced cognitive aids 

integration, mission planning 

• Adaptive, autonomous operations 

• Force integration, interoperability, 

and information assurance 

• Affordable large-scale software 

• Secure, robust communication 

capability 

• Coordinated multivehicle 

flight/motion 

• Affordable operating and support 

cost, and integrated vehicle health 

management 

• Mobility, rapid deployment, and 

footprint 

• Sortie rate, turn time, and ground 

Operations 

Source: DOD. 

Originally, the UCAV program was tasked with providing an air vehicle 

that would perform both preemptive and reactive SEAD missions 

against fixed and mobile targets that are extremely demanding from 

both a mission and capability perspective. The reactive mission is more 

demanding than the preemptive mission because the UCAV will have less 

time to find and engage mobile targets. When DOD decided to accelerate 

delivery of the initial UCAVs, the program was relieved of meeting the 

requirement for reactive SEAD, making for a better balance between 

requirements and available resources. However, requirements were 

subsequently added that increased the challenge of matching requirements 

with resources. These requirements include an electronic attack mission 

and increased combat range and endurance. 

• Electronic attack: DOD’s electronic attack mission is currently 

performed by the Navy’s aging EA-6B Prowler aircraft. Electronic 

attack confuses enemy radars with electronic jammers. In 2001, the 

Navy conducted an analysis of alternatives for replacing the Prowler. 
Page 10 GAO-03-598 UCAV Program's Success 

Air Combat Command planners determined that the UCAV could fill 

portions of this role quickly and added the requirement to the program. 

As currently structured, the program does not plan to demonstrate 

electronic attack technologies on UCAV demonstrator or prototype 

vehicles before product development begins. According to program 

officials, the biggest additional challenge associated with this change 

is the integration of existing electronic attack technologies into a 

low observable air vehicle. Program officials are also concerned that 

downsizing and repackaging current electronic warfare technology 

to fit into a smaller space, with sufficient cooling and power, and 

incorporating antennas and other apertures into the low observable 

signature of the UCAV may pose additional challenges. Program 

officials also stated that the addition of electronic attack adds 

uncertainty to overall program costs. It may reduce the number of 

initial UCAVs planned for initial production because additional work 

will be required to integrate this capability into air vehicles, given the 

current schedule and funding. 

• Longer range and endurance: According to program officials, Air Force 

leadership would like to have a larger UCAV with longer range and 

greater endurance than that currently being designed in the X-45B to 

perform strategic lethal strike and nonlethal intelligence, surveillance, 

and reconnaissance missions. However, increasing UCAV’s range 

forced the program to abandon a key design concept expected to lower 

operating and support costs significantly over that of a manned 

aircraft—one of the program’s original critical requirements. The initial 

UCAV concept was a design that allowed the wings to be detached 

from the air vehicle and stored in a crate for up to 10 years, a concept 

which was expected to contribute to a greater than 75 percent 

reduction in operation and support costs. When needed, the UCAV 

could be shipped to the theater of operations, assembled, and readied 

for use. Adding range and endurance required redesigning the air 

vehicle with fixed or permanently attached wings, in order that the 

inside of the wings could be used as fuel tanks. This would allow the 

UCAV to carry more fuel and give it the ability to fly farther. Since the 

wings would no longer be detachable, the long-term storage approach 

had to be abandoned. 

The schedule for the UCAV program has changed several times during the 

pre-acquisition phase. In 2000, the Air Force anticipated that product 

development would start in 2007 and initial deliveries would begin in 2011. 

After several schedule changes, the Air Force set product development in 

2004 and initial delivery of aircraft in 2007. (See table 2.) The net effect of 

Schedule Compression 

Created Greater Technical 

and Cost Risks 
Page 11 GAO-03-598 UCAV Program's Success 

the changes was a 3-year reduction in time to mature technologies before 

product development. This reduction created the potential for costly and 

time-consuming rework in product development since the Air Force would 

still be in the process of maturing technologies as it undertook other 

product development activities. Moreover, the concurrency that comes 

with the schedule changes would have left little room for error. 

Table 2: Chronology of Changes to the Air Force UCAV Acquisition Program Schedule Since 2000 

Program 

strategy as of 

End of technology and 

military utility 

demonstrations (FY) 

Start product 

development (FY) Initial deliveries (FY) UCAV capabilities 

2000 2007 2007 2011 

Preemptive SEAD; reactive 

SEAD 

2001 2006 2005 2010 

Preemptive SEAD; reactive 

SEAD 

Explanation of change: To meet Air Force expectations for delivering capabilities to the war fighter earlier than 2011, the product 

launch date was moved up by 2 years to 2005 and initial delivery up 1 year to 2010. 

2002 2006 2003 2007 

Preemptive SEAD 

Explanation of change: The schedule was changed by direction of the Office of the Secretary of Defense to further accelerate delivery 

of initial operational UCAVs to the customer. The program attempted to balance this decision by deferring the most challenging 

requirements for conducting reactive SEAD against mobile targets to a future version of UCAV. 

Late 2002 2006 2004 2007 

Preemptive SEAD; 

Electronic attack; 

Extended range 

Explanation of change: The timeline was changed to address added requirements for electronic attack and extended range. While 1

year was added to the start of product development, the date for initial deliveries did not change. 

Source: GAO presentation of program data. 

Under the original schedule, the UCAV program would essentially have 

3 more years prior to the beginning of product development to test and 

mature technologies. As a result, all 15 of the technologies, processes, 

and system attributes would be at low risk by the launch of product 

development indicating a match between requirements and resources. 

By contrast, under the late 2002 schedule, the program would not have 

enough time to mature technologies to a low risk prior to the launch of 

product development in 2004. In fact, most technologies, processes, 

and system attributes would still be either medium or high risk by the 

time product development was launched indicating that requirements 

exceeded resources. 

The overlap of technology development and product development, 

introduced by the acceleration of product development, also raised risks 

for the UCAV program. The late 2002 schedule allowed less time for 

discovering and correcting problems that may have arisen during 
Page 12 GAO-03-598 UCAV Program's Success 

technology demonstrations prior to product development launch. 

Importantly, all of the air vehicle military utility demonstrations would 

have been completed after the beginning of product development. Under 

the original schedule most of these demonstrations would have been 

completed prior to the start of product development. 

Increasing the overlap of technology development and product 

development added risk to the program. Problems found during 

those demonstrations might have to be fixed during product 

development—problems made more likely given the lower maturity 

level of the key technologies. Figure 4 shows that the concurrency 

between technology development and product development increased 

by approximately 18 months under the late 2002 schedule—from a 

6-month approximate overlap to a 24-month approximate overlap. Also, 

this acceleration increased the program risk for the start of product 

development from all low to mostly medium risk for the 15 technologies, 

processes, and system attributes being tracked. 
Page 13 GAO-03-598 UCAV Program's Success 

Figure 4: Effect of Accelerated Product Development Start on Program Risk 

As figure 4 indicates, the UCAV technology and product development 

phases had been shortened from a plan with little concurrency between 

technology and product development to a plan with significant 

concurrency between the two. The push to deliver the product sooner 

compressed the time in which technologies will be matured and integrated 

into the UCAV weapon system. The resulting approximate 24-month 

overlap between technology and product development caused by 

accelerating the beginning of UCAV’s product development program had 

the potential to create “late cycle churn,” or the scramble to fix significant 

problems discovered late. We have found that when problems are 
Page 14 GAO-03-598 UCAV Program's Success 

uncovered late in product development, more time and money is required 

to rework what is already finished.7

The Office of the Secretary of Defense recently restructured the UCAV 

program to a joint program structure to meet the needs of the Navy as 

well as the Air Force. The Office of the Secretary of Defense cancelled 

plans to build the X-45B prototypes and now anticipates that the joint 

UCAV program will focus on a family of vehicles derived from the larger 

Boeing X-45C and Northrop Grumman X-47B prototypes designs. The 

details of the program are still being decided, but it appears likely that 

while content will increase, the start of product development will be 

delayed. This approach represents a substantial improvement over the 

late 2002 plan in that it lowers risks significantly. However, keeping 

requirements and resources in balance and funding intact until product 

development starts will be a challenge. 

The proposed prototypes will be larger than the X-45A or X-45B and thus 

more capable of supporting requirements for greater combat range and 

endurance. Also, both the proposed X-45C and X-47B prototypes will have 

a larger wing area, allowing them to carry increased payload and internal 

fuel. Just as the X-45B would have been more capable than the X-45A, the 

X-45C is projected to be more capable than the X-45B as shown in Table 3 

below. We did not obtain specific data on the X-47B prototype. 

Table 3: Comparisons of UCAV Variants 

 X-45A X-45B X-45C 

Weight 12,000 lb. 21,000 lb. (approx.) 35,000 lb. 

Length 26.3 ft. 32 ft. 36 ft. 

Wingspan 33.8 ft. 47 ft. 48 ft. 

Payload 1,500 lb. 2,000 lb. 4,500 lb. 

Ceiling 35,000 ft. 40,000 ft. 40,000 ft. 

Speed 0.75 Mach 0.85 Mach 0.85 Mach 

Endurance/combat 

radius 

450 NM w/30 

minutes loiter 

850 NM w/30 minute 

loiter (w/added 

internal fuel) 

1100–1300 NM 

w/30 minute loiter 

Source: DOD. 

 7

 U.S. General Accounting Office, Best Practices: A More Constructive Test Approach 

Is Key to Better Weapon Systems Outcomes, GAO/NSIAD-00-199 (Washington, D.C.: 

July 31, 2000). 

Recent DOD Decision 

to Restructure 

Program Can 

Reduce Risks 
Page 15 GAO-03-598 UCAV Program's Success 

Further, by adopting a design that increases internal space on the air 

vehicle, DOD could more readily incorporate electronic attack equipment 

and other sensors and avionics. In addition, the plan would reintroduce 

competition into the UCAV program by assessing two different designs. 

This competition would increase DOD’s ability to pursue the best technical 

solution. On the other hand, acquisition cost for the larger air vehicles are 

expected to increase as will operating and support costs due to the 

abandonment of the storage-in-the-box concept. Also, meeting the 

Navy’s need for carrier-based operations could place additional demands 

on the air vehicle design. Figures 5 and 6 show illustrations of Boeing and 

Northrop Grumman proposed joint UCAV designs. 

Figure 5: Computer Rendition of the Boeing X-45C 
Page 16 GAO-03-598 UCAV Program's Success 

Figure 6: Computer Rendition of the Northrop Grumman X-47B 

In addition, more time will be added under the joint program to conduct 

demonstrations by delaying the start of product development by several 

years. Some of this added time—up to a year—will be needed to develop 

and deliver the new prototypes. As shown in figure 7, delaying the 

beginning of product development could reduce technical risks since DOD 

would have more time to test prototypes. 
Page 17 GAO-03-598 UCAV Program's Success 

Figure 7: Effect of Delayed Product Development Start on Program Risk 

However, these delays may postpone initial operational capability 

beyond what DOD and the Congress originally anticipated, which 

was at the end of the decade. But recognizing this upfront to put the 

program on a sounder footing may be preferable to proposing a 

higher risk approach—like the 2002 plan—that is more susceptible 

to unplanned delays. 

Drawing on the experience of the UCAV to date as well as other programs, 

DOD will face challenges in keeping the requirements for the new joint 

design balanced with available resources. One challenge relates to 

requirements. As mentioned above, more demands could be made of the 

air vehicle to meet the needs of both the Air Force and the Navy. Prior to 

the new joint approach, the Navy’s top mission for the UCAV has been 

conducting intelligence, surveillance, and reconnaissance. When 

considering the Air Force’s missions of reactive and preemptive SEAD and 

electronic attack, it is foreseeable that the program will face pressures to 
Page 18 GAO-03-598 UCAV Program's Success 

meet multiple missions. One approach to meeting this challenge is to delay 

the start of product development until resources—such as technology 

maturity—are available to meet all requirements. This would delay the 

program significantly and could raise funding issues. Alternatively, 

adhering to an evolutionary acquisition approach and developing the 

different mission capabilities in sequence could meet the challenge, so 

that the initial capability can be fielded sooner. 

Another challenge relates to funding. Past and present programs have 

been susceptible to such funding issues. Moreover, other programs 

that dwarf the UCAV program—such as the F-22 and the Joint Strike 

Fighter—will be competing for investment funds at the same time. 

We have found in earlier work8

 that although the Office of the Secretary 

of Defense provides some funding for advanced technology development 

efforts, the military services and defense agencies are ultimately 

responsible for financing the acquisition and support of equipment or 

items that result from the efforts. At times, however, the military services 

have not wanted to fund the transition process. This action either slowed 

down the acquisition process or resulted in no additional procurements. 

Specifically, military services have not wanted to fund technologies 

focusing on meeting joint requirements because those technologies do 

not directly affect their individual missions, and there are specific projects 

that they would prefer to fund. At the same time, Office of the Secretary 

of Defense officials told us that they lack a mechanism for ensuring that 

decisions on whether to acquire items with proven military utility are 

made at the joint level, and not merely by the gaining organizations, and 

that these acquisitions receive the proper priority. 

The UCAV has already experienced some funding challenges. Recently, 

during preparations for the fiscal year 2004 budget cycle, the Air Force 

budget proposal eliminated all UCAV funding beyond that needed to finish 

work on two prototypes already on contract. The Air Force based this 

action on its belief that the X-45B UCAV was too small for the role the 

Air Force believed was most needed. 

 8

 U.S. General Accounting Office, DEFENSE ACQUISITIONS: Factors Affecting 

Outcomes of Advanced Concept Technology Demonstrations, GAO-03-52

(Washington, D.C.: Dec. 2, 2002 
Page 19 GAO-03-598 UCAV Program's Success 

To keep the UCAV program on track, the Office of the Secretary of 

Defense stepped in to resolve requirements and funding challenges and 

maintained a strong oversight over it. While the Office of the Secretary 

of Defense increased the challenge by accelerating the delivery date for 

the first UCAVs, it allowed the Air Force to defer the reactive SEAD 

requirement and fended off more radical changes to the UCAV’s missions. 

In addition, the Office of the Secretary of Defense has taken the lead in 

brokering the agreement on the joint program proposal, adding 

development time to the proposal and working out a joint effort that could 

result in a single design for the Air Force and Navy. Sustaining the role 

played by the Office of the Secretary of Defense is likely to be important to 

meeting future challenges the UCAV may face. 

UCAVs offer a potential for DOD to carry out dangerous missions without 

putting lives at stake and to find cost-effective ways of replacing DOD’s 

aging tactical aircraft fleet. However, up until recently, pre-acquisition 

decisions had collectively increased requirements and reduced resources, 

putting the program in a riskier position to succeed. The decision to create 

a joint program could make for a better program if the gap between 

resources and requirements can be closed. The joint program faces a 

challenge in managing the demands of multimission requirements with 

the desire to field an initial capability in a reasonable time. Accepting 

increased requirements and accelerating fielding at the same time, as was 

previously done, will hinder the ability of the joint UCAV program to 

succeed. The program also faces the challenge of sustaining funding 

support from both services at a time when it is competing against other 

large aircraft investments. Regardless of which direction the new program 

takes, the role played by the Office of the Secretary of Defense will 

continue to be instrumental in helping to negotiate requirements, to assure 

the right resources are provided, and to make further difficult tradeoff 

decisions throughout the program. 

We recommend the Secretary of Defense develop an acquisition approach 

for the joint UCAV program that enables requirements and resources to 

be balanced at the start of product development. This approach should 

provide mechanisms for brokering the demands of multiple missions, for 

ensuring that the product developer maintains a voice in assessing the 

resource implications of requirements, and for preserving the integrity of 

evolutionary acquisition. Reinstating the use of technology readiness 

levels may be very valuable in facilitating necessary tradeoffs. 

Conclusion 

Recommendations for 

Executive Action 
Page 20 GAO-03-598 UCAV Program's Success 

We also recommend that the Secretary formalize the management role 

performed by his office and the attendant authority to perform that role; 

ensure that the services are fully involved in the process; and work to 

develop an efficient approach to transitioning the UCAV from DOD’s 

technology development environment to the services’ acquisition 

environment so the needs of the war fighter can be met more quickly. 

DOD provided us with written comments on a draft of this report. 

The comments appear in appendix I. DOD provided separate 

technical comments, which we have incorporated as appropriate. 

DOD concurred with our recommendation that the Secretary of Defense 

develop an acquisition approach for the joint UCAV program that 

enables requirements and resources to be balanced at the start of product 

development. It has directed the formation of a Joint Systems Management 

Office to define near-term requirements and to conduct robust operational 

assessments. 

DOD partially concurred with our recommendation that the Secretary 

formalize a management role performed by his office and the attendant 

authority to perform that role; ensure that the services are fully involved 

in the process; and work to develop an efficient services’ acquisition 

environment so the needs of the war fighter can be met more quickly. 

DOD noted that the Secretary is organizing the management function as he 

deems suitable. DOD did state that the department’s UAV Planning Task 

Force would continue to provide oversight over all DOD UCAV program 

activities. We believe this is important because it was this organization 

that was instrumental in refocusing the DOD UCAV effort into a joint 

program that we believe will significantly improve the probability of 

successfully fielding UCAVs. 

To achieve our objectives we examined Air Force UCAV program 

solicitations and agreements, the demonstration master plan, trade 

studies, technology demonstration plans and results, status of critical 

technologies, plans to further enhance maturity of critical technologies, 

and plans to move UCAV to the Air Force for product development. We 

interviewed DARPA and Air Force program managers and technical 

support officials at DARPA program offices in Arlington, Virginia, and the 

Air Force’s Research Lab and Aeronautical Systems Center at Wright 

Patterson Air Force Base, Dayton, Ohio, to document current development 

efforts and the maturity status of critical technologies and other attributes. 

Agency Comments 

and Our Evaluation 

Scope and 

Methodology 
Page 21 GAO-03-598 UCAV Program's Success 

To determine options that may be available to UCAV program managers in 

making changes to requirements or resources, we examined the program’s 

risk assessments of its 15 technologies, processes, and system attributes to 

identify risk associated with beginning product development at different 

points in time. We interviewed Air Force Air Combat Command officials 

at Langley Air Force Base, Virginia, concerning UCAV requirements, and 

air staff officials in Arlington, Virginia, concerning program objectives 

and resources. We also interviewed a number of officials from the 

Office of Secretary of Defense having responsibility for UCAV oversight 

and funding. 

We conducted our work from February 2002 through May 2003 in 

accordance with generally accepted government auditing standards. 

We are sending copies of this report to the Secretary of Defense, the 

Secretaries of the Air Force and Navy, the Director of the Office of 

Management and Budget and other congressional defense committees. We 

will also provide copies to others on request. In addition, the report will be 

available at no charge on the GAO Web site at http://www.gao.gov. 

Please contact me at (202) 512-2811 if you or your staff has any questions 

concerning this report. Key contributors to this report were Mike Sullivan, 

Jerry Clark, Matt Lea, Kris Keener, Travis Masters, Cristina Chaplain, Lily 

Chin, Bob Swierczek, and Maria-Alaina Rambus. 

Paul Francis 

Director, Acquisition and Sourcing Management 
Appendix I: Comments from the Department 

of Defense 

Page 22 GAO-03-598 UCAV Program's Success 

Appendix I: Comments from the Department 

of Defense 
Appendix I: Comments from the Department 

of Defense 

Page 23 GAO-03-598 UCAV Program's Success (120125) 
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